TimerabstractA one-selector stopwatch: run a block, get its elapsed time.
For finer control (start now, read later, compare points), use Instant and Duration directly.
Run the block and answer how long it took, in whole microseconds (an Integer). Measured on the monotonic clock, so wall-clock adjustments cannot skew it.
Timer.time:{ (1..1000).each:{ |i| i } } "* the elapsed microseconds